The present application relates to power outage indicators and, more particularly, to a novel power outage indicator utilizing a smectic liquid crystal display cell.
There has been a long standing need for a low cost power outage indicator which can be particularly utilized in locations which are not readily accessible. It is often important to know if power has been interrupted at a location and, in certain instances, there may be time intervals of up to several weeks before monitoring personnel may be able to check a given location. It is preferable that a power outage indicator utilized under such conditions would be highly visible (have a good contrast ratio), exhibit memory phenomena, operate over a broad range of temperatures and be resettable to allow reuse, in addition to having a relatively low cost.